1.Field of the Invention
The present invention relates to a blank material washing booth and system for washing a blank material in a path of transport for press shaping thereof.
2.Description of the Related Art
One known press shaping method comprises the steps of cutting a coiled material into blank materials of predetermined length, stacking the cut blank materials, and supplying the cut blank materials one by one to a transport path for press shaping by a press machine. Trash such as chips often adhere to the surfaces of the blank materials before pressing. When press shaping is performed with such chips adhered to the blank material surfaces, inappropriate shaping may result. It is therefore necessary to wash the blank materials before press shaping. Certain kinds of blank material washing devices are disclosed in Japanese Patent Publication No. SHO 49-37495, Japanese Patent Laid-Open Publication No. SHO 56-19923 and Japanese Utility Model Laid-Open Publication No. SHO 56-23210.
In the washing device disclosed in Japanese Patent Publication No. SHO 49-37495, trash are scratched off by a roller brush. However, the roller brush is easily worn out by contact with blank material edges and thus needs to be frequently replaced, thereby requiring high maintenance costs and tedious replacement operations. To overcome these problems, one may think of employing a steel brush which can hardly be worn out but this is inappropriate in that the blank materials may be flawed by the steel brush.
The washing devices disclosed in Japanese Patent Laid-Open Publication No. SHO 56-19923 and Japanese Utility Model Laid-Open Publication No. SHO 56-23210 are arranged such that a washing liquid is jetted from a high-pressure injector at trash on the blank materials to thereby remove the trash. However, these devices have a problem in that a suspended mist resulting from jetting the washing liquid leaks out from a washing chamber, thereby deteriorating a peripheral atmosphere.
To this end, the present inventors have proposed in Japanese Patent Laid-Open Publication No. HEI 8-120474 a "Blank Material Washing Device". The proposed device has a chamber disposed midway of a path of transport of a blank material to a pressing machine. The chamber is separated by partition walls into a front chamber positioned upstream of the transport path, a washing chamber disposed midway of the transport path, and a rear chamber disposed downstream of the transport path. The front chamber has a pair of upper and lower pinch rolls serving as feed rollers, and a mist suction port for sucking a suspended mist. The washing chamber includes a pair of washing liquid injection pipes each having a plurality of high-pressure injection or jet nozzles. The rear chamber includes a first and second pair of wringer rolls serving as wipe rollers for wiping off the washing liquid, and a mist suction port. In the proposed device, a suspended mist can be captured by a mist collector through the mist suction ports even when the washing liquid is sprayed onto the blank material under a high pressure, thereby maintaining a surrounding atmosphere in a good condition.
For sufficiently removing persistent contaminants on the blank material by using the device of Japanese Patent Laid-Open Publication No. HEI 8-120474, there is no alternative but to increase the pressure of injection of the washing liquid. However, if the injection pressure is increased, the amount of required washing liquid doubles, thereby increasing the amount of the suspended mist to be dealt with and the amount of the washing liquid to be wiped off. As a result, it becomes necessary for the wringer rolls to be provided in three- or four-stories. This imposes an increased load on the mist collector and hence requires the latter to be large-sized. Further, provision of the wringer rolls in increased stories leads to up-sizing of the washing device. Moreover, to increase the injection pressure of the washing liquid, a pump of large capacity needs to be employed, thereby increasing the cost of installation of the device.